731561425920 has 264 divisors, whose sum is σ = 2729831316576. Its totient is φ = 180076511232.

The previous prime is 731561425913. The next prime is 731561425939. The reversal of 731561425920 is 29524165137.

731561425920 is a `hidden beast` number, since 7 + 3 + 1 + 5 + 614 + 2 + 5 + 9 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11572 + ... + 1209651.

Almost surely, 2^731561425920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 731561425920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1364915658288).

731561425920 is an abundant number, since it is smaller than the sum of its proper divisors (1998269890656).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

731561425920 is a wasteful number, since it uses less digits than its factorization.

731561425920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1221267 (or 1221246 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 45.

It can be divided in two parts, 731561 and 425920, that added together give a triangular number (1157481 = T₁₅₂₁).

The spelling of 731561425920 in words is "seven hundred thirty-one billion, five hundred sixty-one million, four hundred twenty-five thousand, nine hundred twenty".